Numerical simulation of the airflow field in vortex spinning processing

2018 ◽  
Vol 89 (6) ◽  
pp. 1113-1127 ◽  
Author(s):  
Shanshan Shang ◽  
Jianping Yang ◽  
Chongwen Yu
Keyword(s):  
Numerical Simulation ◽  
High Speed ◽  
Stable Process ◽  
Three Dimensional ◽  
Experimental Result ◽  
Initial State ◽  
Suction Force ◽  
Spinning Process ◽  
Airflow Field ◽  
Yarn Tenacity

Three-dimensional numerical simulation of the airflow characteristics during the whole vortex spinning process, including the initial state of the yarn drawing-in process and the normal stable process, were obtained and analyzed. Spinning experiments, with the aid of a scanning electron microscope, were adopted to verify the results of the numerical simulation. The numerical simulation results show that the turbulence phenomenon in the normal spinning process is much more obvious than that in the initial spinning process; the air streamlines move orderly in the initial spinning process, which will produce a strong suction force that will be conducive to drawing the fiber bundle into the nozzle successfully, but the trajectory of airflow is complex in the normal stable spinning process and there is an upstream airflow with the same direction as the rotating airflow to provide extra tension for the yarn, which can improve the strength of the resultant yarn. The spinning experimental result is consistent with the result predicted by numerical simulation. The research further reveals the flow regularity and the turbulent phenomenon of the high-speed rotating airflow, predicts the effect of airflow motion on the spinning effect, and is helpful for stabilizing the spinning process and improving the yarn tenacity.

Numerical simulation of airflow characteristics in the spinning zone at starting time of air-jet spinning machine

2018 ◽  
Vol 89 (12) ◽  
pp. 2342-2352
Author(s):  
Thi Viet Bac Phung ◽  
Akihiro Yoshida ◽  
Yoshiyuki Iemoto ◽  
Hideyuki Uematsu ◽  
Shuichi Tanoue
Keyword(s):  
Fiber Bundle ◽  
High Speed ◽  
Three Dimensional ◽  
Swirl Flow ◽  
Air Pressure ◽  
Suction Force ◽  
Starting Time ◽  
Air Jet ◽  
Spinning Process ◽  
Center Axis

To clarify the formation mechanism of a source of yarn and to discuss the effects of supplied air pressure and exhaust air pressure on the fiber suction force and twist torque at the starting time of the spinning process in an air-jet spinning machine, we simulated, numerically, the three-dimensional airflow pattern without fibers in the spinning zone. Results obtained are as follows: High-speed air jetted through the starting nozzles into the yarn duct in the circumferential direction causes a swirl flow in the yarn duct and a negative pressure region near the center axis of the yarn duct. Hence, air and fibers at the fiber inlet are sucked through the processing duct into the yarn duct. A fiber bundle sucked into the yarn duct rotates, owing to the action of the swirl airflow, and twists the fiber bundle in the processing duct, hence generating a source of yarn. The fiber suction force takes a distribution with a peak against the supplied air pressure and is independent of the exhaust air pressure. The fiber twist torque increases monotonously with supplied air pressure.

scholarly journals Modeling the airflow field of vortex spinning

2021 ◽  
pp. 004051752110569
Author(s):  
Shanshan Shang ◽  
Zikai Yu ◽  
Guangwu Sun ◽  
Chongwen Yu ◽  
R Hugh Gong ◽  
...  
Keyword(s):  
High Speed ◽  
Three Dimensional ◽  
Wall Function ◽  
Great Insight ◽  
Spinning Process ◽  
Turbulent Airflow ◽  
Region Model ◽  
Airflow Field ◽  
Control Volumes ◽  
Insight Into

Vortex spinning technology adopts a high-speed swirling airflow to rotate the fibers with open-ends to form yarn with real twists. The airflow behavior within the nozzle has a great effect on the yarn-formation process. In this study, a three-dimensional calculation nozzle model and corresponding three-dimensional airflow region model were established to enable the numerical calculation; airflow behavior—pressure, velocity, and the turbulent airflow field, and the streamline of airflow—was investigated in the presence of fiber bundles within the vortex spinning nozzle. Hybrid hexahedral/tetrahedral control volumes were utilized to mesh the grids in the calculation region. To consider airflow diffusion and convection in the nozzle, the Realizable k- ε turbulence model with wall function was adopted to conduct the calculation. Dynamic and static pressure values were obtained by numerical analysis to predict the action of the inner surface of nozzle and the wall resistance on the high-speed swirling airflow. The numerical simulation of dynamic airflow behavior can generate great insight into the details of airflow behavior and its distribution characteristics, and is helpful for understanding the spinning mechanism and promoting optimization of the spinning process.

Effect of position of the fiber transport channel on fiber motion in the high-speed rotor

2021 ◽  
pp. 004051752110018
Author(s):  
Rui Hua Yang ◽  
Chuang He ◽  
Bo Pan ◽  
Hongxiu Zhong ◽  
Cundong Xu
Keyword(s):  
High Speed ◽  
Channel Model ◽  
Three Dimensional ◽  
Discrete Phase Model ◽  
Transport Channel ◽  
Rotor Spinning ◽  
Fiber Motion ◽  
Discrete Phase ◽  
Airflow Field ◽  
Fiber Transport

The task of the fiber transport channel (FTC) is to transport the fibers from the carding roller to the rotor. Its geometric position in the spinning machine has a strong influence on the characteristics of the airflow field and the trajectory of the fiber motion in both the rotor and the FTC. In this paper, a three-dimensional pumping rotor spinning channel model was established using ANSYS-ICEM-CFD software with three different positions of the FTC (positions a–c). Further, the simulations of air distribution were performed using Fluent software. In addition, the discrete phase model was used to fit the fiber motion trajectory in the rotor. The simulation results showed that among the three types of FTC, position b is the optimal condition. The gradients of airflow velocity in the channel at position b were greater than those of the other two positions, which is conducive to straightening of the fiber.

Behavior of Bubble in Small Water Tank Used for Food Processing Using Underwater Shock Wave

2011 ◽  
Vol 673 ◽  
pp. 225-230 ◽  
Author(s):  
Hideki Hamashima ◽  
Manabu Shibuta ◽  
Shigeru Itoh
Keyword(s):  
Numerical Simulation ◽  
Shock Wave ◽  
Food Processing ◽  
High Speed ◽  
Underwater Explosion ◽  
Video Camera ◽  
Experimental Result ◽  
Water Tank ◽  
Underwater Shock Wave ◽  
Small Water

The food processing technology using a shock wave can prevent deterioration of the food by heat because it can process food in a short time. Generally, since the shock wave used for food processing is generated by underwater explosion, the load of a shock wave to the food becomes very complicated. Therefore, in order to process safely, it is important to clarify the behaviors of the shock wave and the bubble pulse generated by underwater explosion. In this research, in order to investigate the behavior of the shock wave in the water tank used for food processing, the optical observation experiment and the numerical simulation were performed. In the experiment, the shock wave generated by underwater explosion was observed with the high-speed video camera. The numerical simulation about the behavior of bubble pulse was performed using analysis software LS-DYNA. Comparing and examining were performed about the experimental result and the numerical simulation result. The result of the numerical simulation about the behavior of the shock wave generated by underwater explosion and the shock wave generated by the bubble pulse and the bubble pulse was well in agreement with the experimental result.

scholarly journals NUMERICAL SIMULATION OF AIRFLOW AROUND VEHICLE MODELS

2018 ◽  
Vol 56 (3) ◽  
pp. 370
Author(s):  
Nguyen Van Thang ◽  
Ha Tien Vinh ◽  
Bui Dinh Tri ◽  
Nguyen Duy Trong
Keyword(s):  
Numerical Simulation ◽  
Kinetic Energy ◽  
Three Dimensional ◽  
Aerodynamic Characteristics ◽  
Aerodynamic Forces ◽  
Dissipation Energy ◽  
Ansys Fluent ◽  
Car Model ◽  
Airflow Field ◽  
Fluent Software

This article carries out the numerical simulation of airflow over three dimensional car models using ANSYS Fluent software. The calculations have been performed by using realizable k-e turbulence model. The external airflow field of the simplified BMV M6 model with or without a wing is simulated. Several aerodynamic characteristics such as pressure distribution, velocity contours, velocity vectors, streamlines, turbulence kinetic energy and turbulence dissipation energy are analyzed in this study. The aerodynamic forces acting on the car model is calculated and compared with other authors.

Numerical and Experimental Evaluation of Turbulent Flow in Volute

2003 ◽  
Author(s):  
Akitomo Igarashi ◽  
Kazuyuki Toda ◽  
Makoto Yamamoto ◽  
Toshimichi Sakai
Keyword(s):  
Numerical Simulation ◽  
Cross Section ◽  
Three Dimensional ◽  
Experimental Result ◽  
Centrifugal Fan ◽  
Flow Conditions ◽  
Flow Angle ◽  
Fan Performance ◽  
Centrifugal Fans ◽  
Good Agreement

The performance of centrifugal fans is considerably influenced by the design of tongue at the re-circulation port. The flow in the volute of a centrifugal fan was studied both experimentally and numerically. In this experiment, flow angle, pressure and velocity profiles were measured at a large number of locations in the volute. The flow field in the volute passage was analyzed using Computational Fluid Dynamics. The flow was assumed to be three dimensional, turbulent and steady. The numerical simulation produced qualitatively good agreement with the experimental result. The results from experiment and numerical simulation indicated that the adoption of a re-circulating flow port improved fan performance for all flow conditions. In addition, the existence of strong secondary flow was apparent at the cross-section of the volute passage.

Numerical and Experimental Investigation of Secondary Flow in a High Speed Compressor Stator

1995 ◽  
Author(s):  
Y. Ohkita ◽  
H. Kodama ◽  
O. Nozaki ◽  
K. Kikuchi ◽  
A. Tamura
Keyword(s):  
Numerical Simulation ◽  
Experimental Investigation ◽  
Shear Flow ◽  
Secondary Flow ◽  
Total Pressure ◽  
High Speed ◽  
Experimental Studies ◽  
Three Dimensional ◽  
Three Dimensional Flow ◽  
Performance Recovery

A series of numerical and experimental studies have been conducted to understand the mechanism of loss generation in a high speed compressor stator with inlet radial shear flow over the span. In this study, numerical simulation is extensively used to investigate the complex three-dimensional flow in the cascades and to interpret the phenomena appeared in the high speed compressor tests. It has been shown that the inlet radial shear flow generated by upstream rotor had a significant influence on the stator secondary flow, and consequently on the total pressure loss. Redesign of the stator aiming at the reduction of loss by controlling secondary flow has been carried out and the resultant performance recovery was successfully demonstrated both numerically and experimentally.

Experiment and Numerical Simulation of Extrudate Swell in the Polymer Extrusion Process

2011 ◽  
Vol 314-316 ◽  
pp. 401-404 ◽  
Author(s):  
Min Zhang ◽  
Chuan Zhen Huang ◽  
Guo Wen Chen ◽  
Yu Xi Jia
Keyword(s):  
Numerical Simulation ◽  
High Speed ◽  
Three Dimensional ◽  
Simulation Method ◽  
Extrusion Process ◽  
High Speed Photography ◽  
The Finite Element Method ◽  
Polymer Extrusion ◽  
Extrudate Swell ◽  
Rate Profile

The extrudate swell of the polymer extrusion process was studied with the experiment and simulation method. The extrudate swell process was recorded by the high-speed photography apparatus. The swell rate at the different time was calculated. It is found that the extrudate swell rate increase at the first five seconds. The maximum swell rate is about 4.37%. The three-dimensional numerical simulation model of the experiment die path was founded. The extrusion process including the extrudate swell was simulated used the Finite Element Method. Such simulated results as the velocity vector, the shear rate profile and the end of the swell zone were analyzed. The extrudate swell end got by the simulation is similar with the experiment result.

NUMERICAL SIMULATION OF THE VAPOR FILM COLLAPSE BEHAVIOR AT VAPOR EXPLOSION WITH THREE-DIMENSIONAL LATTICE GAS THERMAL-HYDRAULIC AUTOMATA METHOD

2003 ◽  
Vol 17 (01n02) ◽  
pp. 189-192
Author(s):  
DAISUKE TOCHIO ◽  
YUTAKA ABE ◽  
YOSUKE MATSUKUMA ◽  
HIDEKI NARIAI
Keyword(s):  
Numerical Simulation ◽  
Phase Change ◽  
Lattice Gas ◽  
Three Dimensional ◽  
Experimental Result ◽  
Vapor Film ◽  
Lattice Gas Automata ◽  
Numerical Result ◽  
Collapse Behavior ◽  
Film Collapse

In order to clarify the dominant driving force of complex vapor film collapse behavior, numerical simulation is performed with three-dimensional fifteen-velocity lattice gas automata method. As the result, numerical result is qualitatively different from the experimental result. On the other hand, numerical simulation of vapor film collapse behavior is performed with three-dimensional fifteen-velocity lattice gas automata method including phase-change effect. As the result, numerical result is qualitatively similar to the experimental results. Comparison between the experimental result and the numerical result confirms that experimentally observed vapor film collapse behavior is dominated not by fluid motion but by phase change.

scholarly journals Effect of Forming Parameters on Profile Thinning of Flexible 3D Multi-Point Stretch Bending

Metals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1581
Author(s):  
Zhongyuan Shi ◽  
Yi Li ◽  
Jicai Liang ◽  
Ce Liang
Keyword(s):  
Numerical Simulation ◽  
Process Parameters ◽  
Orthogonal Experiment ◽  
Three Dimensional ◽  
Simulation Software ◽  
Experimental Result ◽  
Range Analysis ◽  
Stretch Bending ◽  
Rectangular Profile ◽  
Aluminum Profiles

The ABAQUS finite element simulation software is used to simulate the flexible multi-point three-dimensional stretch bending process of aluminum profiles. The effect of process parameters on the web thickness of rectangular profile in flexible multi-point three-dimensional stretch bending is studied by orthogonal experiment and range analysis. The process parameters used in the experiments include pre-stretching value, post-stretching value, the number of multi-point dies and friction coefficient. The optimal combination of process parameters is obtained by numerical simulation and experimental verification. When the aluminum profile is completed flexible multi-point stretch bending according to the best parameters, the thickness thinning of outer web and inner web is the smallest. The experimental result is closed to the numerical simulated results. The effectiveness of the numerical simulation is verified by the corresponding experimental methods.

Sign in / Sign up

Export Citation Format

Share Document